Barr revealed the news in an interview with The Daily Beast about her new documentary Roseanne for President! which follows her ill-fated 2012 quest for the White House. In the film, which premiered at the Tribeca Film Festival this weekend, the actress and activist advocates and even uses medical marijuana, which she says helps to treat her condition.

"It’s a good medicine, you know," Barr told the website. "I have macular degeneration and glaucoma, so it’s good for me for that because I have pressure in my eyes. It’s a good medicine for a lot of things."

The comedy legend said doctors don’t have a timetable for when she might go totally blind, but she is already noticing decreased vision.

"My vision is closing in now," Barr explained. "It’s something weird. But there are other weird things. That one’s harsh, 'cause I read a lot, and then I thought, 'Well, I guess I could hire somebody to read for me and read to me.' But I like words and I like looking. You do what you have to do. I just try and enjoy vision as much as possible—y'know, living it up. My dad had it, too."